Compound action tool

ABSTRACT

The specification discloses a compound action tool of the pliers type which is commonly employed for crimping purposes. The tool comprises a pair of handles each having a laterally extending ear at one end with the ears overlapping and pivotally connected. An arm is pivoted to the end of each handle and terminates in a jaw. Each arm has a lobe extending laterally towards the other arm. Each arm is formed with an arcuate slot in the region of the lobe with each slot receiving a pin carried by the other lobe. The end edge of each lobe is formed as a curved cam surface which is engaged by a portion of the jaw on the other arm which projects therefrom and overhangs the cam surface.

United States Patent Allen COMPOUND ACTION TOOL [72] Inventor: Irving Allen, Westbrook, Conn.

[73] Assignee: Sargent 8:, Company, New Haven,

Conn.

[22] Filed: May 25, 1971 [21] App]. No.: 146,633

[51] Int. Cl. ..B21d 9/08 [58] Field ofSearch .72/409, 410; 29/203 H,

29/203 HC', 203 HM, 203 HT, 212 R, 212 D; 17347451, 385, 386, 405, 406, 41s

[56] References Cited UNITED STATES PATENTS 7 2,829,547 4/1958 Barnes ..72/409 2,074,239 3/1937 Rush ..8l/349 832,804 10/1906 Pearson ..-......8l/349 2,274,945 3/1942 Van Keuren ..81/349 FOREIGN PATENTS'OR APPLICATIONS 427,495 5/1911 Franco s .....,72/409 [151 V 2l 704,620 451 Dec. 5, 197 2 France ..s1/41s Great Britain ..72/4 10 Primary Examiner-Charles W. Lanham Assistant ExaminerMichael J. Keenan Attorney-Schellin & Hoffman [571 ABSTRACT The specification discloses a compound action tool of the pliers type which is commonly employed for crimping purposes. The tool comprises a pair of han- "ales"aaelriiavinga'iatefinyenema; can? one end with the ears overlapping and pivotally connected. An

arm is pivoted to the end of each handle and terminates in a jaw. Each arm has a lobe extending laterally towards the other arm. Each arm is formed with an arcuate slot in the region of the lobe with each slot receiving a pin carried by the other lobe. The end edge of each lobe is formed as a curved cam surface which is engaged by a portion of the jaw on the other arm which projects therefrom and overhangs the cam surface.

.5 a. 4 Claims, 5 Drawing Figures P'A'TEN'TEDnEc 5 I972 3. 704.620

sum 1 or 2 INVENTOR IRVING A LLEN ATTORNEYS FIG. 5.

PKTENTEDnsc 5 I972 SHEET 2 BF 2 INVENTOR IRVING ALLEN ATTORNEYS COMPOUND ACTION TOOL The present invention relates to tools of the pliers type which are employed for crimping purposes and is concerned primarily with such a tool which includes a compound action for transferring compressive forces on the handles to jaws which move together and under conditions of high mechanical advantage and in which the movements of the jaws are properly oriented until work is engaged by the jaws.

BACKGROUND OF THE INVENTION Tools of the general type with which the present invention is concerned are now in widespread use. A tool of one class includes as characteristic and essential elements a pair of handle levers each having a laterally extending ears at one end with the ears on the two levers overlapping andpivotally connected. A jaw carrying arm is pivotally connected at one end to each lever at the end adjacent the ear thereon. Each of vthese arms is formed with a pivot hole and crosspieces extend across the arms and have pins received in the holes. Thus a certain degree of mechanical advantage is provided. A third pivot pin is located in the region of the crosspieces and is received in recesses in the edges of the arms. This pin provides for a rocking motion of the arms and serves to assist the movement of the jaws as they move together to engage the work.

The now known tools of this type are fairly complex and the mechanical advantage offered thereby is determined by the distance between the pivotal connection of an arm to a handle lever and the pivot pin. If a tool is to be compact the mechanical advantage is limited by this distance.

OBJECTS OF THE INVENTION With the foregoing conditions in mind the present invention has in view the following objectives:

1. To provide a tool of the characteraforesaid which is highly simplified. I i 2. To provide a tool of the type noted which is compact and which includes a novel compound action which affords a maximum of mechanical ad vantage for the size limitation of the compact mechanism. 3. To provide in a tool of .the kind describe, a new and improved arrangement for orienting the movement of the jaws as they approach the work. Various other more detailed objects and advantages of the invention such as arise in connection with carrying out the above noted ideas in a practical embodiment will in part become apparent and in part be hereinafter stated as the description of the invention proceeds.

SUMMARY OF THE INVENTION I The foregoing objects are achieved by providing a compound action tool comprising a pair of handle levers each having a laterally extending ear at one end with the ears overlapping and pivotally connected. Pivoted on the end of each handle lever at'the end adjacent to the ear thereon is an arm which is formed with a jaw at its free end. Each of these arms is formed with a laterally extending lobe which overlaps the other arm. Each arm is formed with an arcuate slot that receives a guide pin on the lobe of the other arm. Each lobe has an end edge including a curved ca'm surface. Each jaw is formed with a portion that projects from the plane of a side face thereof and engages the cam surface on the lobe of the other arm. The engagement of these overhanging portions of the jaws with the cam surfaces orients the movement of the jaws as they approach the work to be gripped by the jaws.

For a full and more complete understanding of the invention reference may be had to the following description and accompanying drawings wherein:

FIG. 1 is an elevation of a compound action tool embodying the precepts of the present invention with the jaws in closed position.

FIG. 2 is a side elevation of the tool looking in a direction normal to the showing of FIG. 1.

FIG. 3 is a cross section through the pivotal connection of the handle levers, being taken on the plane of the line 3-3 of FIG. 1.

FIG. 4 is a detailed elevation, taken on an enlarged scale depicting the jaws in opened position; and

FIG. 5 is a detailed perspective, also on an enlarged scale of the jaws and lobes, bringing out particularly the relation of the overhanging portions of the jaws and the cam surfaces on the lobes.

Referring'now to the drawings the compound action tool of this invention is shown as including a pair of handle levers 10 and 11. While these levers may be of any construction which affords the ears results they are illustrated asbeing of the channel structure depicted in FIG. 3. Thus lever 10 is of U cross section and preferably of sheet metal providing a wall 12 that is flat throughout its extent and joined by a bend 13 to a second wall 14 that has an offset ear 15 integral therewith. Lever 11 is also of U cross section and includes a flat wall 16 that is fitted beneath ear 15, a bend l7 and a wall 18 having an offset ear 19 integral therewith which overlies wall 12. Walls 12 and 16 and ears 15 and 19 are formed with aligned openings which receive a pivot in the form of a rivet 20 having upset ends 21 whichmaintain the assembled relation.

As shown in FIG. I handle levers l0 and 11 are provided with a hand grip 22 which may be of any appropriate material.

Walls 12 and 14 of lever 10 are continued beyond ear 15 to provide a pair of spaced endtabs 23, one of which appears in FIG. 1. Likewise, walls 16 and 18 are continued beyond car 19 to provide a pair of spaced end tabs 24.

An arm is identified in its entirety at 25. It includes an end tab 26 that is fitted between end tabs 23 and pivotally connected thereto by a pivot pin in the form of a rivet 27 (FIG. 2) having headed ends 28 which maintain the assembled relation. Arm 25 is formed with an offset centered portion 29 formed with an arcuate slot 30 (FIG. 4) and from which laterally extends a lobe 31 which is integral with offset portion 29. Lobe 31 carries a guide pin 32 which also may be in the form of a rivet with headed ends for a purpose to be later described. Arm 25 terminates in a jaw 33 having a portion 34 which projects from a side face thereof and, in a sense, overhangs central portion 29. Lobe 31 has an end edge including a curved cam surface 35.

A second arm designated generally 36 has an end tab 37 that isfitted between end tabs 24 on lever I1 and is pivotally secured thereto by headed rivet 38. It includes which is engaged by overhanging portion 34 of jaw 33.

Arm 36 terminates in a jaw 44 having a projecting or overhanging portion 45 which rides on cam surface 35 of lobe 31. I

In operation, with handle levers l and 11 in a spaced or open position as illustrated in FIG. 4, jaws 33 and 44 are spaced. Pin 42 is in the one end of slot-30, pin 32 is in one end of slot 40 and overhanging jaw portion 34 and 45 are in contact with cam surfaces 35 and 43. As levers and 11 are moved towards one another the jaws 33 and 44 are similarly moved and oriented in such movement by the overhanging jaw portions-riding on the cam surfaces which they engage.

At the same time pins 32 and 42 move towards the other ends of slots 30 and 40 and a high degree of mechanical advantage is achieved by the effective distance between pivot pin 28 and guide pin 32 on arm .25 and between pivot pin 38 and guide pin 42 on arm 36. The headed-ends of guide pins 32 and 42 maintain the lobes in sliding engagement with the offset central portions of the arms respectively.

Whilepreferred specific embodiments of the invention are hereinbefore set forth, it is to be clearly understood that the invention is not to be limited to the exact constructions, mechanism and devices illustrated and described because various modification of these details may be provided in putting the invention into practice.

What is claimed is:

1. in a compound action tool:

a. a pair of handle levers each having an ear extending laterally therefrom adjacent to one end thereof,

b. said ears overlapping and being pivotally connected, 1

an arm pivotally connected at oneend to each of said levers at the end thereof adjacent to the ear thereon, each arm having a central portion formed with an arcuate slot and a lobe extending laterally therefrom with the lobe on one arm overlying the central portion of the other arm,

. a guide pin carried by each lobe and received in the slot in the other arm,

f. each lobe having an edge including a curved cam surface,

. a jaw on each arm at the end thereof, and

. a projecting portion on each jaw overhanging and engaging the cam surface or the lobe of the arm other than that by which the jaw is carried.

2. The compound action tool of claim 1 in which the central portion of each arm is offset with respect to the jaw thereon.

3. The compound action tool of claim 1 in which each handle lever has a pair of spaced end tabs and each arm has an end tab received between the spaced end tabs-of a handle lever with the pivotal connections being provided by pivot pins passing through aligned opening in the end tabs.

4. The compound action tool of claim 3 in which the central portion of each arm is offset with respect to the end tab and jaw thereon. 

1. In a compound action tool: a. a pair of handle levers each having an ear extending laterally therefrom adjacent to one end thereof, b. said ears overlapping and being pivotally connected, c. an arm pivotally connected at one end to each of said levers at the end thereof adjacent to the ear thereon, d. each arm having a central portion formed with an arcuate slot and a lobe extending laterally therefrom with the lobe on one arm overlying the central portion of the other arm, e. a guide pin carried by each lobe and received in the slot in the other arm, f. each lobe having an edge including a curved cam surface, g. a jaw on each arm at the end thereof, and h. a projecting portion on each jaw overhanging and engaging the cam surface or the lobe of the arm other than that by which the jaw is carried.
 2. The compound action tool of claim 1 in which the central portion of each arm is offset with respect to the jaw thereon.
 3. The compound action tool of claim 1 in which each handle lever has a pair of spaced end tabs and each arm has an end tab received between the spaced end tabs of a handle lever with the pivotal connections being provided by pivot pins passing through aligned opening in the end tabs.
 4. The compound action tool of claim 3 in which the central portion of each arm is offset with respect to the end tab and jaw thereon. 